乳粉中叶黄素的测定方法及稳定性的影响

建立一种测定配方奶粉中叶黄素质量分数的高效液相色谱方法，采用YMCTM色谱柱（5μm，250mm ×4．6mm），流动相为甲醇-甲基叔丁基醚（85∶15），等度洗脱，流速为1．0ml/min，检测波长445nm，该方法在0．3～6．0mg/L的质量范围内线性良好（ R＝0．99993），基质加标水平为0．30μg/g、0．60μg/g、3．0μg/g时，回收率分别介于96．52％～98．10％之间，相对标准偏差介于1．31％～4．66％之间，方法检出限为0．05μg/g，说明该方法可行。同时，研究一定的温度、加热时间及光照等条件对乳粉中叶黄素稳定性的影响，得出随着温度提高、加热时间及光照时间的延长，叶黄素含量呈递减趋势，且变化显著（ P＜0．05）。

Study on the Determination and Effect of Stability of Lutein in Milk Powder

In order to set up a HPLC method for determination of lutein in milk powder ,The analysis was carried on a YMCTM （ 5μm, 250mm ×4.6mm ） column, whose mobile phase was methyl tert-butyl ether （85∶15）,flow-rate was 1.0mL/min,and chromatographic runs were montitored at 445nm.The results showed that between 0.3-6.0mg/L,the linearity of the method was good （R=0.99993）.Under the spiked levels of 0.30μg/g,0.60μg/g,3.0μg/g,the recoveries ranged from 96.52%~98.10%,the relative deviation were between 1.31%~4.66%,and the limit of detection was 0.05μg/g.So this method was feasible .At the same time,the impact of temperature ,heating and illumination on the stability of lutein was investigated .The results showed that along with the heightening of the temperature ,and the extension of the time of heating and illumi-nation,the content of the lutein decreased progressively ,and the change was significant （P〈0.05）.